Axially arranged rotary threshing or separating systems have long been in use in agricultural combines for threshing crops to separate grain from crop residue, also referred to as material other than grain (MOG). Such axially arranged systems typically include at least one cylindrical rotor rotated within a concave or cage, the rotor and surrounding concave being oriented so as to extend forwardly to rearwardly within the combine.
In operation, crop material is fed or directed into a circumferential passage between the rotor and the concave, hereinafter referred to as a rotor residue passage, and is carried rearwardly along a generally helical path in such passage by the rotation of the rotor as grain is threshed from the crop material. The flow of crop residue or MOG remaining between the rotor and concave after threshing is typically discharged or expelled by the rotating rotor at a rear or downstream end of the rotor and the rotor residue passage in a generally downward, or a downward and sidewardly, direction, in what is a continuation of the helical path of movement of the crop residue within the rotor residue passage between the rotor and concave.
Such flow thus proceeds from the rotor residue passage into a discharge opening at the downstream end of the rotor and into a further discharge passage that extends downwardly and somewhat rearwardly into a crop residue treatment and distribution system located below and rearwardly of the rear end of the threshing system. Such crop residue treatment and distribution system typically includes a rotary beater or chopper or other apparatus, hereinafter generally referred to as a rotary residue chopper, that processes the residue to reduce it to smaller pieces and propels such finer residue rearwardly within a rear end of the combine for either discharge from the combine through a rear opening onto a field, such as for windrowing, or into a spreader assembly, hereinafter referred to more simply as a spreader, for distribution thereby, such as in a swath on the field. In many typical applications, the spreader may include and utilize a pair of counter-rotating spreader head assemblies, typically driven by hydraulic spreader or drive motors, disposed in a side-by-side arrangement, to spread the crop residue flow that is being provided thereto from the rotary residue chopper. In some instances, a further chopper may also be included as part of the spreader to reduce the crop residue into still smaller particles before distribution by the counter-rotating spreader head assemblies.
Due to the nature of operation of the rotor, the design of the rotor and concave, and the helical movement of the crop residue within the rotor residue passage, the flow of crop residue from the rotor residue passage into the discharge opening is often greater on the downward sweep side of the rotor than on the upward sweep side, as a consequence of which the resulting crop residue flow across the width of the discharge opening is often uneven across the width of the discharge opening. Such uneven flow has often, in the past, been permitted to proceed through the discharge passage to the rotary residue chopper and therethrough to the crop residue spreading system.
When crop residue is to be spread over a field, the width of the header, it is often considered desirable that the crop residue be distributed as evenly or uniformly over the field as possible. Such uniformity of distribution is desirable because uneven crop residue distribution on a field can lead to temperature and moisture gradients detrimental to even growth of future crops on the field. Uneven distribution can make it difficult for crops to utilize nutrients and can impact the effectiveness of agricultural chemicals. Moreover, large discontinuities of crop residue can lead to plugging and other functional problems with tillage and/or planting equipment.
One factor that has been found to significantly affect the ability of a spreader to distribute crop residue evenly or uniformly over a field has been the transverse or side-to-side variation in the crop residue inflow into and through the rotary residue chopper and to the spreader. In such regard, it has been found that when the amount of crop residue presented at or to one side of the rotary residue chopper has been about equal to the amount of crop residue presented at or to the other side of the rotary residue chopper, a more even and uniform distribution of crop residue in a swath on a field can be achieved by the side-by-side operation of the spreader head assemblies. On the other hand, when the presented amounts are unequal or unbalanced, the distribution onto the field has been more uneven and less uniform.
It has also been found that the side-to-side introduction of crop residue from the rotor into the discharge opening and to the crop residue chopper can be affected by a variety of variables and conditions. Generally, residue from different crops, such as wheat and corn, will flow differently, and different rotor rotation speeds will typically be used for different crops. For example, small grains such as wheat and other grasses will typically be threshed at a relatively high rotor speed, for instance, 600 to 1000 revolutions per minute (rpm), and will produce residue containing a large volume of small stalks of straw, whereas corn will typically be threshed at a relatively slow rotor speed, for instance, less than 400 rpm, and produce crop residue containing a mixture of bulky stalk segments, cob fragments and large leaves. For a given crop, differences in plant maturity and weather conditions can affect size, moisture content, and other characteristics of crop residue so as to have varying flow and distribution characteristics.
Due at least in part to the above described variables and conditions, it has been observed that the transition of crop residue flow from the threshing system to the crop residue treatment and distribution system can vary significantly from harvesting operation to harvesting operation, and even during the course of a given harvesting operation. In particular, the side-to-side distribution of the crop residue flow as it proceeds from the rotor residue passage into the discharge opening and towards the rotary residue chopper may often be variable, that is, the flow to one side of the chopper may be heavier than to the other side, such that the chopper will propel more crop residue towards one side of the following spreader, resulting, in turn, in uneven crop residue distribution over a swath on the field being harvested.
Several devices and constructions have been developed in attempts to address the foregoing problems, including the adjustable deflector constructions such as are described in U.S. Pat. No. 7,186,179 and co-pending U.S. patent application Ser. No. 11/712,047, which are incorporated herein by reference thereto. The deflector constructions of such applications have been positioned with a deflector plate thereof hingedly or pivotally mounted at the downstream end of the rotor, and adjustment thereof to effect a redistribution of the crop residue at such location, upstream from the rotary residue chopper, has generally been effected either manually or by a positioning control system operated by a user.
It has been recognized that, in view of the variability of the crop residue flow in differing situations and with different crops, improved performance and reliability can be achieved by adjusting the position of such a deflector plate from time to time during operation of the combine so as to better balance and equalize the amounts of crop residue being distributed by the side-by-side spreader assemblies of the crop residue spreading system under then-attendant conditions. To this point in time, however, any adjustment has typically required or been as a result of human intervention by a user at such times as the user deems appropriate, either in the manual adjustment by the user of the deflector plate or by operation of a positioning control system in response to an input of some type by the user or operation by such user of a control element, such as a control button or switch.
Consequently, unless or until a user or operator has observed that the spread of the crop residue has become unbalanced, the adjustable deflector has typically been maintained in an established position, which position may not have been an ideal position over a period of time for directing the flow of crop residue from the threshing system to effect a balanced spreading of the crop residue by the spreader head assemblies of the spreader. What has therefore continued to be sought has been a system and method for better controlling the positioning of an adjustable deflector for effecting better balancing and equalization of the amounts of crop residue being distributed by the side-by-side spreader assemblies of the crop residue spreading system, preferably on an automated basis and without the need for operator intervention.